Chain connecting link

ABSTRACT

A connecting link for power transmission chain is disclosed having two identical half link sub-assemblies. Each sub-assembly comprises a link plate having a laterally-extending pin at one end thereof and an aperture formed at the other end thereof. Two of these sub-assemblies are designed to be assembled into a connecting link by having the pin on one sub-assembly extend through the aperture in the link plate of the other sub-assembly. The sub-assemblies are held in assembled position by two spring clips which are attached to both pins at either side of the connecting link.

United States Patent 1 Montano 1 Jan. 9, 1973 154] CHAIN CONNECTING LINK[75] Inventor: Joseph V. Montano, West Hartford,

Conn.

[73] Assignee: Litton Industrial Systems, Inc.

[22] Filed: Oct. 20, 1970 [21] Appl. No.: 82,249

[52] U.S. Cl ..74/258 [51] Int. Cl ..Fl6g 13/02 [58] Field of Search..74/258, 254, 245 R, 251 R [56] References Cited UNITED STATES PATENTS1,121,053 12/1914 Terry ..74/258 617,716 1/1899 Caldwell 2,775,15612/1956 lmse et a1. ..74/258 X Primary Examiner-Leonard H. GerinAttorney-John D. Boos and John D. Lister [57] ABSTRACT A connecting linkfor power transmission chain is disclosed having two identical half linksub-assemblies. Each sub-assemb1y comprises a link plate having alaterally-extending pin at one end thereof and an aperture formed at theother end thereof. Two of these sub-assemblies are designed to beassembled into a connecting link by having the pin on one sub-assemblyextend through the aperture in the link plate of the other sub-assembly.The sub-assemblies are held in assembled position by two spring clipswhich are attached to both pins at either side of the connecting link.

10 Claims, 3 Drawing Figures CHAIN CONNECTING LINK BACKGROUND OF THEINVENTION This invention relates to power transmission chain and, moreparticularly, to a connecting link for coupling and uncoupling rollerchain together. The term roller chain refers to a chain which isgenerally provided with rollers but the term, as currently employed inthe trade and as employed herein, also includes a similar chain designwithout individual rollers.

Roller chain conventionally comprises alternating roller links and pinlinks coupled together. The roller links are usually composed of twolink plates interconnected by two bushings which are press-fitted intoapertures in each of the plates. The pin link is formed with pinsextending through the bushings of adjacent roller links and which pinsare interconnected by two pin link plates, each of which is providedwith two apertures and into which are fitted each of the pins. The pinsare generally secured in position by spinning or swaging both ends ofeach pin or, alternatively, by spinning or swaging the ends on only oneside of each pin but with a hole drilled in the other end thereof so asto receive a cotter pin. In order to readily facilitate coupling anduncoupling separate lengths of such roller chain together, or to form asingle length of chain into an endless chain, connecting links arefrequently employed.

As shown in U. S. Pat. No. 580,449, these connectinglinks are typicallyformed with a pin link sub-assembly, a cover plate, and a single springclip retaining device. The sub-assembly comprises a link plate havingapertures formed in the ends thereof and into which apertures arepress-fitted pins which extend outwardly from one side thereof. The pinsin the sub-assembly are designed to extend through the end bushings ofthe lengths of chain which are to be coupled together, and the coverplate, which is formed with apertures in the ends thereof, is designedto be slip-fitted over these pins and held in position by a singlespring clip. In a like manner, opposite ends of a single length of chaincan be coupled together so as to form an endless chain.

While this type of connecting link has proved suitable for manyapplications, it has created certain serious problems when employed ondrive chain which is frequently subjected to severe vibration, severecentrifugal forces, overloads, and/or frequent shockloads, or which isemployed with misaligned sprockets. As an example, a number of theseconditions are frequently experienced by drive chains employed onmotorcycles. When one or more of these conditions are experienced, ithas been found that the spring clips are frequently pushed off of thepins or are broken so as to thereby enable the cover plate to work itsway off the ends of the chain pins and enable the pin link sub-assemblyto become separated from the drive chain. If this should occur duringthe operation of the drive chain, it could potentially damagesurrounding equipment and could injure personnel in the area. In thecase of the motorcycle usage, there have been instances where suchconnecting link failure has occurred, resulting in serious injury topersonnel on the motorcycle.

Additional prior art connecting links such as disclosed in U. S. Pat.Nos. 632,856 and 3,379,072 have been designed but are thought to beunsatisfactory either because of the above-described problems or becausethey do not readily facilitate coupling and uncoupling of the chain.Likewise, additional patents, such as U. S. Pat. No. 741,455, disclosechain links which can be readily coupled and uncoupled together butwhich have a relatively greater number of parts that can be lost andwhich are generally thought to be more expensive to produce. Thus, therestill remains a definite need for a connecting link having a smallnumber of parts which can be readily coupled and uncoupled together andwhich greatly resists failure during severe operating conditions.

SUMMARY OF THE INVENTION According to the present invention, there isprovided a connecting link having two identical half linksub-assemblies. Each sub-assembly comprises a link plate having alaterally extending pin press-fitted into an aperture at one end of thelink plate and a second aperture formed at the other end thereof whichis sized to be a slide-fit with the pin of the other sub-assembly. Theends of each pin are formed with grooves therein and the pin is designedsuch that the grooves are positioned on the outside of the link plateswhen the sub-assemblies are assembled together. The sub-assemblies areassembled together with the pin of each link plate extending through theaperture in the other link plate. A spring clip is snapped into thegrooves of both pins at each side of the connecting link so as to securethe subassemblies in their assembled position.

Accordingly, one object of the present invention is to provide aconnecting link which is readily coupled and uncoupled together andwhich can be employed in connection with chain which is subjected tosevere operating conditions.

Another object of the invention is to provide a connecting link having arelatively small number of parts which are designed to be readilycoupled and uncoupled together.

A third object of the invention is to provide a connectinglink designedto employ two spring clip retaining means holding the connecting link inassembled position and requiring the removal of both retaining meansbefore the connecting link can be disassembled.

BRIEF DESCRIPTION OF THE DRAWING Other objects, advantages, and novelfeatures of the present invention will become apparent in the followingdescription of the invention when considered in connection with thedrawings herein.

FIG. 1 is a plan view ofa length ofa chain embodying the presentinvention with parts broken away and sectioned for ease of understandingand showing an exploded view of the connecting link.

FIG. 2 is a plan view similar to FIG. 1 but showing the connecting linkfully assembled and secured by the two spring clips.

FIG. 3 is a side view of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT As seen in the drawing, theroller chain is made up of alternating roller links 10 and pin links 12coupled together so as to form a series of articulated links. Eachroller link is composed of two link plates 14 interconnected by bushings16 whichare press-fitted into the ends of link plates 14. Rotatablymounted on bushings 16 are rollers 18. The pin links 12 are formed withpins 22 extending through, and being rotatably mounted in, the bushingsof the adjacent roller links and with the pins 22 being press-fittedinto apertures formed in the ends of the pin link plates 20. The ends ofthe pins are swaged as seen at 22a.

The connecting link comprises two identical half link sub-assemblies30-30, only one of which will be described in detail; however, it willbe understood that corresponding parts of the second sub-assembly aremarked with the same reference numerals but are fol lowed by a primemark (e.g., 30'). Each sub-assembly has a link plate 32 formed with apin 34 projecting laterally therefrom at one end thereof and which plateis also formed with an aperture 36 therein at the other end thereof. Inthe preferred embodiment, pin 34 is made as a separate piece and ispress-fitted into an aperture 38 formed in the link plate. Aperture 36has a slightly larger diameter than aperture 38 which facilitatesassembling and disassembling two identical sub-assemblies into aconnecting link as will hereinafter be described. 3

At each end of the pin a shallow groove 40, 40a is formed about the neckthereof. As seen in FIG. 1, the pin extends through plate 32 such thatthe first groove 40 at one end of the pin is immediately adjacent theoutside face 32a while the second groove 40a at the other end of the pinis spaced some distance from the inside face 32b of the link plate 32.The pin is dimensioned such that when two identical sub-assemblies areassembled together, the second groove 40a is immediately adjacent theoutside plate face 32a of the cooperating sub-assembly.

As seen in FIG. 1, the pin 34 of the sub-assembly is designed to extendthrough the bushing of the end link that is to be connected. The pin 34'of a second identical sub-assembly is designed to extend through thebushing of theother end link that is to be coupled to the first endlink. Each sub-assembly is then brought together with a pin 34 extendingthrough aperture 36' while pin 34 extends through aperture 36. Whileapertures 38, 38" are sized so as to create a press fit, with pins 34,34' respectively, apertures 36, 36 have a diameter, or aresized, so asto create a slide fit or a drive fit with the pins 34, 34 respectively,and in this manner assembling and disassembling is readily facilitated.

When the two identical sub-assemblies are assembled together, asshown inFIG. 2, the sub-assemblies are secured in position by two detachableretaining means 42. 42 which in the preferred embodiment areconventional split spring, retaining clips that are snapped onto bothpins 34, 34' at either side of the assembled connecting link.Specificially, clip 42 is shown attached to the pins on one side of theconnecting link immediately adjacent outside face 32a and positioned ingrooves 40', 40a, while clip 42 is attached to the pins on the otherside of the connecting link, immediately adjacent outside face 32a, andpositioned in grooves 40, 40. Each of the spring clips are designed tobe readily snapped on and off the ends of the pins in a manner known inthe art. It will be apparent that each spring clip independently holdsthe assembled sub-as- 4 semblies together, and that both spring clipsmust be removed before the assembled sub-assemblies can be separated.

It will also .be apparent from the above description that two identicalhalf link sub-assemblies comprise the connecting link of the presentinvention. There are no separate pins, bushings, etc., which can beaccidentally lost when the connecting link is in a disassembled state.

Furthermore, and more importantly, the specific subassemblies aredesigned so as to receive two detachable retaining means which arecoupled to both pins in the connecting link. It is this arrangementwhich helps insure against accidental disassembly of the connecting linkwhen employed on a chain which is employed in severe operatingconditions. Finally, the use of spring clips as the detachable retainingmeans readily facilitates the quick assembly and disassembly of theconnecting link.

Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. For example, in thepreferred embodiment the link plate and pin which comprise eachsub-assembly are disclosed as being made separately and then joinedtogether; however, it will be readily apparent that the link plate andpin can be made as an integral unit by, for example, conventionalpowdered metallurgical techniques. It is therefore to be understood thatthe invention may be practiced otherwise than as is specificallydescribed herein.

What is claimed is:

1. In combination, a connecting link for use with roller chain, saidconnecting link comprising two half link sub-assemblies, each of saidsub-assemblies formed with a link plate and a pin extending laterallytherefrom, each of said link plates formed with a first aperturetherein, saidsub-assemblies being assembled together with the pin of onesub-assembly extending through the first aperture in the link plate ofthe other sub-assembly, tworetaining means securing the assembledsub-assemblies together, each of said retaining means being detachablycoupled to thepinsv of both sub-assemblies.

2. The-combination defined in claim 1 wherein each of said link platesare formed with a second aperture therein, the pin and link plate ofeach sub-assembly being assembled with the pin thereof extendingthrough, and being press-fitted in, the second aperture of the linkplate of the sub-assembly;

3. The combination defined in claim 2 wherein both sub-assemblies areidentical, and wherein the first aperture in the link plate of eachsub-assembly is sized so as to readily receive the pin of the othersub-assembly.

4. The combination defined in claim 2 wherein each of said. pins areformed with a groove at each end thereof and wherein each of saidretaining means is a spring clip, one of said spring clips being coupledonto one end of the pins of both sub-assemblies at one side of theassembled connecting link, the other of said spring clips being coupledonto the other end of the pins of both sub-assemblies at the other sideof the assembled connecting link, each of said spring clips beingpositioned in at least a portion of one of the grooves formed in each ofsaid pins.

5. The combination defined in claim 1 wherein each of said retainingmeans is a spring clip, one of said spring clips being coupled onto saidpins at one side of said connecting link and the other of said springclips being coupled onto said pins at the other side of said connectinglink.

6. A roller chain having articulated links and a connecting linkinterconnecting the end links of the chain so as to form the rollerchain into an endless chain, said connecting link comprising two linkplates, each of said link plates having a pin projecting laterallytherefrom and formed with a first aperture therein, said connecting linkbeing assembled together with the pin of one sub-assembly extendingthrough the first aperture in the link plate of the other sub-assembly,two detachable retaining means securing the assembled connecting linktogether, and each of said retaining means being coupled to the pins ofboth sub-assemblies.

7. The combination defined in claim 6 wherein the link plates of eachsub-assembly are formed with a second aperture therein, the pin and linkplate of each sub-assembly being assembled with the pin thereofextending through, and being press-fitted in, the second aperture of thelink plate of the sub-assembly.

8. The combination defined in claim 7 wherein both sub-assemblies areidentical, and wherein the first aperture in the link plate of eachsub-assembly is sized so as to readily receive the pin of the othersub-assembly.

9. The combination defined in claim 7 wherein each of said pins areformed with a groove at each end thereof and wherein each of saidretaining means is a spring clip, one of said spring clips being coupledonto one end of the pins of both sub-assemblies at one side of theassembled connecting link, the other of said spring clips being coupledonto the other end of the pins of both sub-assemblies at the other sideof the assembled connecting link, each of said spring clips beingpositioned in at least a portion of one of the grooves formed in each ofsaid pins.

10. The combination defined in claim 6 wherein each of said retainingmeans is a spring clip, one of said spring clips being coupled onto saidpins at one side of said connecting link and the other of said springclips being coupled onto said pins at the other side of said connectinglink.

1. In combination, a connecting link for use with roller chain, saidconnecting link comprising two half link sub-assemblies, each of saidsub-assemblies formed with a link plate and a pin extending laterallytherefrom, each of said link plates formed with a first aperturetherein, said sub-assemblies being assembled together with the pin ofone sub-assembly extending through the first aperture in the link plateof the other subassembly, two retaining means securing the assembledsubassemblies together, each of said retaining means being detachablycoupled to the pins of both sub-assemblies.
 2. The combination definedin claim 1 wherein each of said link plates are formed with a secondaperture therein, the pin and link plate of each sub-assembly beingassembled with the pin thereof extending through, and being press-fittedin, the second aperture of the link plate of the sub-assembly.
 3. Thecombination defined in claim 2 wherein both sub-assemblies areidentical, and wherein the first aperture in the link plate of eachsub-assembly is sized so as to readily receive the pin of the othersub-assembly.
 4. The combination defined in claim 2 wherein each of saidpins are formed with a groove at each end thereof and wherein each ofsaid retaining means is a spring clip, one of said spring clips beingcoupled onto one end of the pins of both sub-assemblies at one side ofthe assembled connecting link, the other of said spring clips beingcoupled onto the other end of the pins of both sub-assemblies at theother side of the assembled connecting link, each of said spring clipsbeing positioned in at least a portion of one of the grooves formed ineach of said pins.
 5. The combination defined in claim 1 wherein each ofsaid retaining means is a spring clip, one of said spring clips beingcoupled onto said pins at one side of said connecting link and the otherof said spring clips being coupled onto said pins at the other side ofsaid connecting link.
 6. A roller chain having articulated links and aconnecting link interconnecting the end links of the chain so as to formthe roller chain into an endless chain, said connecting link comprisingtwo link plates, each of said link plates having a pin projectinglaterally therefrom and formed with a first aperture therein, saidconnecting link being assembled together with the pin of onesub-assembly extending through the first aperture in the link plate ofthe other sub-assembly, two detachable retaining means securing theassembled connecting link together, and each of said retaining meansbeing coupled to the pins of both sub-assemblies.
 7. The combinationdefined in claim 6 wherein the link plates of each sub-assembly areformed with a second aperture therein, the pin and link plate of eachsub-assembly being assembled with the pin thereof extending through, andbeing press-fitted in, the second aperture of the link plate of thesub-assembly.
 8. The combination defined in claim 7 wherein bothsub-assemblies are identical, and wherein the first aperture in the linkplate of each sub-assembly is sized so as to readily receive the pin ofthe other sub-assembly.
 9. The combination defined in claim 7 whereineach of said pins are formed with a groove at each end thereof andwherein each of said retaining means is a spring clip, one of saidspring clips being coupled onto one end of the pins of bothsub-assemblies at one side of the assembled connecting link, the otherof said spring clips being coupled onto the other end of the pins ofboth sub-assemblies at the otheR side of the assembled connecting link,each of said spring clips being positioned in at least a portion of oneof the grooves formed in each of said pins.
 10. The combination definedin claim 6 wherein each of said retaining means is a spring clip, one ofsaid spring clips being coupled onto said pins at one side of saidconnecting link and the other of said spring clips being coupled ontosaid pins at the other side of said connecting link.